Jordan Slabinski always referred to everyone by "Slab," is an antihero in Mr. Young.
He is the school bully. He uses intimidation to get what he wants out of people, but he revealed to Derby one day that he isn't naturally aggressive, but that he has to use aggressiveness, because that's what people expect out of him. He bullies Derby, but is willing to help him, because he thinks of Derby as a friend. It is also mentioned in Mr. Candidate that he has a psychotic personality disorder.
Slab is generally your stereotypical bully, rude, arrogant, lazy, dim, and uninterested in studying, Slab is often shown to be aggressive and violent, and will commonly threaten others to get his way, he also commonly abuses others, sometimes for no other reason than he feels like it.
He does however have a more civilised side, and is shown to be interested in Astronomy, and Ballet, he also loves classical music, and was very angry, when Derby misplayed a symphony.
He is also implied not bully out any dislike or particular reason, only either to keep up his reputation, or because he feels like it, as he can go from being friendly to bullying someone at the drop of a hat.
Derby is Slab's primary bully target, and, strangely, Slab's closest friend. He, Derby and Echo would usually be the ones to pull pranks. Slab shows a level of commitment to Derby's happiness, as shown in "Mr. Spring Break", where he put on a dress and acted like Derby's wife so that they could go to Sanduras together.
Slab is generally mean to Adam (the show's main protagonist), and intimidates Adam into doing what he wants (he is the main antagonist of the first episode). Slab seems bored by Adam's class, and constantly undermines Adam's authority. Slab does seem to show some level of respect to Adam occasionally, and seems to care about Adam. But, for the most part, Slab treats Adam like any other 14-year-old child. Slab also does not have any clue whoever Adam attempts to compliment, when obviously it is Echo, and he acts as if Adam was complimenting Slab.
Echo is Slab's closest female friend. They don't interact with each other much, but when they do, it's generally a good interaction. Slab never bullies Echo directly.
Mr. Tater (the show's primary antagonist) and Slab have a long standing feud, Slab loves pranking, or causing trouble for Mr. Tater, in return Mr. Tater is commonly the one who busts Slab.